Microscope



Nov. 21, 1944. H. N. OTT

MICROSCOPE Filed June 23, 1943.

s Sheets-Sheet 1 E Q 1 M 2% a ATTORNEYS Nov.'2l, 1944. H N, on 2,363,080

MICROSCOPE r Filed June 23, 1943 5 Sheets-Sheet 2 INVENTOR ATTORNEYS i adjustment mechanism.

Patented Nov. 21, .1944

., UNITED STATES PATENT; OFFICE MICROSCOPE Harvey Ott, Buffalo, NY. Application June 23, 1943, Serial No. 491,931

16 Claims.

This invention relates to improvements in microscopes and particularly to means for adjusting the body tube of a microscope relatively to the object or specimen.

One of the objects of this invention is to pro vide a microscope of this type with means of improved construction for effecting the fine, and

coarse adjustments of the body tube relatively to the specimen.

Another object is to provide a microscope with fine and coarse adjustments of improved, construction which requires only a single hearing .or slidable connection of the armof the microscope relatively to themain frame thereof. A further vide a bearing block having a pinion shaft journalled therein for effecting the'coarse adjustment of the arm relatively to the bearing block and which pinion shaftis frictional ly gripped way of example, some embodiments of this in-,

vention: v v

Fig 1 is a fragmentary side elevation, partly in section, of a microscope embodying this invention. 1

Fig; 2 is a transverse sectional plan. view thereof, on line 2-2, Fig. l. i r

Figs. B and 4are sectional plan views thereof, respectively on lines 3 3 and 4-4, Fig. 1.

'Fig. 5 is a sectional elevation thereof, on line 5-5,Fig.3. 3 Fig. ,6 is a fragmentary elevation thereof, partly in section, on line 6--6, Fig. 4.

Fig. '7 is a fragmentary sectional elevation thereof, on line 1-1, Fig.1. I Fig. 8 is a fragmentary sectional elevation of a microscope provided with fine and coarse adjustments of modified construtztionfthe section being taken on line 8- -8, Fig. 10;

Fig. 9 is a. transversesection thereof, on line by the bearing block to prevent relative movement of the bearing block with regard to the arm except by turning of said pinion shaft. A furnism and which: is movable with the arm relatively to the main frame by means of the fine A further object of this invention is to provide a microscope having the fine and coarse adjustment buttons ordisks mounted to rotate about a concentric axis fixed with relation to the frame i of the microscope. A further object 10f this invention is to provide fine and coarse adjusting shafts which are mounted on the, inclination joint of the microscope. Another, object is to provide fine and coarse adjustment shafts concentric with each' other and with the inclination joint.

A further object is to provide an adjusting mechanism for a microscope in which amovable connection is provided in the portion of the Fig. 10 is a fragmentary sectional elevation thereof, approximately on line Hllll, Fig.8.

Fig. 11 is a fragmentary sectional plan view angles as may be desired. The main frame has ax considerable portion thereof adjacent to and above theinclination jointrecessed or hollow to house the coarse and fine adjustment mechanisms, and consequently, this portion of the main frame has side walls 14, to thefront end of which the lower portion of anupright guide portion l'la with one or more objectives 20. 2| represents the stage of the microscope, which is securely mounted on the main frame l1, and 22 represents a condenser forprojecting light to the object. The condenser is mounted on a carriage or sub-stage 23 which may be adjustable relatively to the mainframe of the "microscope by meansmof an adjustment wheel or button 23a in any suitable or. desired manner, no adjustment mechanism being shown in the drawings.

.A mirror 24 may also be mounted on the carof the arm It! may extend between the side walls By means of this con M of the main frame. struction, a bearing of more than usual length is provided which ensures accuracy of movement of the arm relatively tothe frame of the microscope and also results in a rigid and durable construction. 1 As will be hereinafter explained,

both the fine and coarse adjustments .emp'iby this bearingto adjust the arm l8.

' The inclination joint may be formed in any suitable manner, and in thelconstruction shown,

trunnions are journalled in bearings provided in the pedestals It, as clearlyshown in Figs. 4 and 6'. These trunnion have flanges 3| which are suitably secured to the main frame member ll and the side walls l4 thereof, for example, by screws as shown, and the trunnions extend into bearings formed partly in the pillars I6 and partly in the bearing caps 33 of these pillars and the necessaryfriction for holding the body tube and the main frame in the desired inclination may be attained by tightening the screws which clamp the :bearingcaps 33 to the pillars. By means of this construction, the hollow trunnions 39 have a sufficiently large internal diameter so that the coarse and line adjustment shafts may.extend into the trunnions.

In the particular construction illustrated, the

coarse adjustment is effected by means of a pair of hollow shafts 35 and 36, both of these shafts being provided. at their outer ends with coarse adjustment actuating means, such as disks or buttons31.- The hollowcoarse adjustment shaft 35 is of materially'smaller diameter than the internal diameter of 'the'trunnion39and a sleeve 38 of a bevel gear 39 extends about the coarse adjustment shaft 35 and is secured thereto, and

this sleeve bears in the hollow trunnion. The other coarse adjustment shaft-36 hasa portion All ofreduced diameter to which a connecting sleeve 4!. is secured. The other, end of this sleeve is secured to a portion of the hollow coarse ad- 4 justment shaft "35 I which extends beyond the bevel gear sleeve 38, so that the two coarse adjustm'ent shafts are rigidly connected, thus per- 'mitting the coarse adjustment to be actuated by either disk or button 31. for connecting the two coarse adjustment shafts Any other means and for mounting a bevel gear thereon may be provided, if desired, v

The bevel pinion 39 meshes with a bevel pinion 43 having a shaft 44'journa1led on the main frame ll. This gear and its shaftmay be held against endwise movementby means-of an annular groove 45 into which an end of a screw or pin 46 enters. The shaft 44 has a spur gear 43 secured thereto, thebevel gear 43 and the spur gear48 being arranged in a recess 50. formed forthatpurpose in the main frame vll. The spur gear 48, .as clearly shownin Fig. 1, mesheswith another spur gear 52 which may be secured :to

or formed integral with a. shaft 53; The .end of:

flit

this shaft remote from the gear 52 is arranged for limited vertical movement, which may be provided for by mounting the end of the shaft on which the gear 52 is arranged on the ball portion 54 of a bearing pin' 55 suitably secured in the main frame II, the ball portion '54 extending into a hole or recess concentrically arranged with reference to the gear 52. Any other construction for permitting this shaft 53 to swing to a limited. extent may be provided, if desired.

The part of the shaft 53 remote-from the gear 52 is connected to a coarse adjustment pinionv shaft 51 by mean of a universal joint 58 of .any suitable or usual construction. The pinion shaft 51 has a pinion 59 mounted thereon which meshes with a rack 60 suitably secured on the.

arm -l8 of the microscope, and this pinion shaft 51 issuitably journalled in a floating bearing block or element 6! interposed between the adjusting means and the arm l8, and which will be hereinafter more fully described. The rack 60 is-mounted in .a side .of. .an,.elongated recess 63 formed in the arml8, .see also Fig. 5. The recess is made large enough to. receive the pin ion v59 and inorder to hold the pinion in correct mesh with the rack 60, the pinion shaft 51 is preferably provided with an extension 64 which fitsin anelongatedgroove65 formedin the front wall of the groove 63. Consequently, it will be .obvious that when the coarseadjustment button is turned,. rotation will be transmitted through ;the bevel gears 39 and 43 and the spur gears'48 and52 to the pinion 59, and the pinion meshing with the rack- 60 will produce up and down movement of thearm |8 of the microscope. Since the floating bearing block or interponentelement 6| is movable relatively to the main frame of the microscope, itwill be obvious that by'means of the. construction described, a floatin driveoonnectionlis provided in the coarse adjustment mechanism, by means of which rotation is transmitted .to the shaft .5Lregardless of the position of the floating bearing block.

The floatingbearing block (5.! in which the coarse adjustmentpinion shaft .5T--bears, is slid- I ably mountedon the arm l8 and has no sliding connectionwith orbearing on themain frame of the microscope. Also thisblock is frictionally connected with the microscope arm so that the arm. is movedrelatively to the block only by turning the coarse. adjustmentmechanism.

This'frictio-nal connection.may be'made in any suitable manner and inthe construction illustrated, the floating. bearing block is preferably made of two pieces which. are secured together by means. of screws 61. The bearing for the shaft 51 is formed partly ineach of the two parts i of the floating bearing block, and the two parts of the block are so constructed and clamped together by the screws that theyjgrip the pinion shaft 5? with the desired tension so that the weight of thearm. l8 and the parts mounted thereon cannot cause therack to impart turning movement to the pinion 59. The friction on the shaft 51, however, permits the same to be-turnedby means of the coarse adjusting mechanism.

The floating bearing block is slidably mounted on the'arm |8 of the microscope irrany suitable .7 "or desiredmanner, and in the construction'illustrated, the arm has a dove-tailed guidetrack 69, Figs. .3 and 4; The twoparts of the floating bearing blockengage'this. dove-'tailed'track so that the arm l8 may move relativelyto the floating bearing. :blccls duringilthe .actuation: of the the fine adjustment mechanism and is also movable by means of this mechanism for effecting fine adjustment of the arm. Since thefloating bearing block isfrictionally held on the arm l8, it will be obvious that by raising or lowering this block,

the arm -|8 and the parts mounted thereon will also be raised and lowered. H i

. "The fine adjustment mechanism includes a fine adjustment shaft 10 having a screw-threaded portion H and is provided at opposite ends with fine adjustment actuating means, such as buttons or knobst'lZ. This shaft bears in the hollow coarse adjustment shafts and is rotatable relatively to theseshafts. The screw-threaded portion H of the. shaft engages a'nut 14 arranged within the connecting sleeve 4| which connects the two hollow coarse adjustment shafts. This nut is held against rotation relatively to the connecting sleeve 4|, for example, by providing this sleeve with longitudinal slots" I5. Screws 16 extend through the slots 15 and also connect a fine adjustment ring 11 to the fine adjustment nut 14, see also Fig.7. As a result of this construction, it will be noted that when the coarse adjustment buttons or disks 3! are turned, the fine adjustment shaft 10 will turn with the coarse adjustmerit shafts and with the connecting sleeve 4|.

Consequently, the nut 14 and the fine adjustment ring 11 wi11 turn withthe fine adjustment screw,

so that the turning of the screw by means of the coarse adjustment shafts will produce no move ment of the nut "or ring 11 lengthwise of these shafts and of the sleeve 4|. When, however, the fine adjustment shaft is turned whilethe coarse adjustment shafts remain stationary, the threaded portion H of the fine adjustment shaft causes the fine adjustment nut 14 to move lengthwise of the sleeve 4| and this lengthwise motion is transmitted through thescrews 16 to thefine adjustment ring 'I'Lsothat this ring will then iblock 6|, see also Fig.1. Consequently, by swinging thelever 8|], the floating bearing block 6| is moved either up or down,and this movement is transmitted to the arm l8 of the microscope be.-

cause of the frictional grip of the pinion shaft .51 by the two parts of the floating bearing block 16L .The inner ends of the coarse adjustment shafts and 3B serve to limit the movement of :the fine adjustment nut 14, and consequently, also [the movement of the floatingbearing block 6|. i

In order to. supplement the weight of the arm .|8 and the floating bearing block to ensure a contact between the projecting or toe portion 83 of thebearingblock and the fine adjustment lever 82, a spring 85 is preferably employed; the lower end of which is hooked on apart of the main frame l1 and the upper end of which is connected with the floating bearing block 5|.

. .By means of the construction shown, it willbe :notedthatl the coarse andfine adjustment shafts .are rotatable aboutam axis concentric with the axis of the inclination joint of the microscope,

and. consequent1y,the positions of these fine and coarse adjustment buttons do not change, regardless of the adjustment of theinclinationjoint or of the arm of the. microscope. These adjustment buttons are located well below the level of the stage 2| in such position that they are readily accessible to the hands of the user of the microscope While his hands rest upon the table or support on which the microscope stands. By means of. the universal joint inthe coarseadjustment gear train, the slight up and down movement of the floating bearing block BI is made possible.

81 represents a grip or guard for the microscope, the lower part of which has a flange 88 which is secured to the upper face of the main frame H. The guard also hasside flan es. 89 which extend along the sides of the arm l8 and are secured to the upright guide portion Ila of the main frame. ,Themicroscope maybe readily lifted or moved about by grasping this guard,

which also formsaprotection for the lower portion of the arm I8 of the microscope,

It will be noted from the foregoing description I j that the microscope is provided with a long slid ing bearingbetween the arm l3 and the. main frame through the medium of the upright guide portion Ila, This long bearing provides strength andaccuracy of adjustment and it will also. be noted that this bearingserves both for the movement of the coarse adjustment mechanismand the fineadjustment mechanism so that only one bearing between the main frame and the arm is required.

In the microscope shown in Figs. 8 to 11, a somewhat similar microscope is shown having a different coarse adjusting mechanism. In this figure, represents the main frame of the microscope which is pivotally mounted on the upright pillars of the base 96, and the main frame has an upright guide portion 91 secured thereto somewhat in the same manner as described in connection with Figs. 1 to 7, the main frame in the construction shown being partly hollow and bored to receive parts of the coarse and fine adjustment mechanism. The arm 98 of the microscopehas a long sliding bearing on thejupright guide portion 9'! similar to that shown in Figs. 1 to '7 and also a guard 99 is provided which is secured to the main frame and extends about the arm, This microscope has a floating bearing block or element fill, which is interposed between the adjusting means and the arm of the microscope and which is slidably mounted onthe arm 98, the arm in the construction shown being provided on the rear face thereof with a dove-tailed portion I0 I, with which the two parts of the floating bearing block or element Hi0 engage. The arm also has a rack I03 secured thereto with which a pinion I04 meshes, this pinion being journalled in the floating bearing block and arranged in a hollowed-out portion or recess in this block, the pinion meshing with a gear I05 similarly journalled and arranged in the floating bearing block. The floating bearing .block may be readily drilled and reamed to form the bearings for the shafts of these two gears, and the two parts of the block then separated and the bearing holes secured to the main frame 95. Two hollow 4i i w aeesgoso coarse. adjustment shatter 1 lift and r l='l:2'- are :arranged within the: tr unnioris lI'IIIandu are: actus ated by 1 meansof coarse adj ustmenn actuating means; suchwas disks Or buttmisr IN: The two coarse adjustment shafts are connected by means ofx a sleeve I I 5 similar to thesleeve 41:. showrr in Figs, .1 to 7 and? a beveled pinion I'Ii'I is mounted on: the coarse adjustment shaft Il-2 andal'so sea cured: tothe sleeve M5. so that this bevel gear may beturned by either: of the coarse adjustment buttons; This bevel; gear meshes withanother bevel gear H3. The beveh gear l l'8'has asho'llow shaft no Which is preferably: formed integral therewith and which iis journalled' to-rot'ate in a cylindrical bore formed in the main frame 85*.

In order to transmitmotion of the coarse adjustment shafts to the gear I'Il5 inthe floating bearing block, a suitable floating driveconnection is provided so that rotation of the'ooarse ad'- ju'stment shaft will be transmitted to the floating bearing block in. any position that the block may occupy while being adjusted by means-of the fine adjustment mechanism. In the construction shown in- Figs. 8 to 11, this floating drive comprises a drive member I20 which may be apart of or secure-d tothe hollow shaft II9 of the bevel gear III In the construction shown, thisdrive memberisprovided with a slot I2lextending acrossthe. upper portion thereof, as shown in Figs, 8 and 11, and this member I20 is secured to thehollow shaft H9 by means of a pin I22. Any other meansfor providing a slot inthe' hollow shaft H9 may be provided;

A shaft I25 of a bevel gear I26 has the lower portion thereof flattened on opposite sides so-that thisportionof the shaft' ma enter into the slot l 'e t'of the drive member I20. The shaft I25 and bevel gear I26 are arranged in the floating bearing member I and the bevel gear I26 meshes with another bevel gear I21; Fig. 9, which is on the same-shaft as the gear H35.v From theforegoing, itwill be obviousthat upon turning either of the coarse adjustmentbuttons I14; the bevel gear H7 will beturned, thus imparting rotary motion to the bevel gear- M8, which in turn I through the floating drive connection including the drive member I20 and the flattened sides of the shaft IZEQimpart' motion through the bevel gears I26 and IZ I to the gears I and- IM, the latter gear meshing with the rack |Il3 secured to thearm 98 of the microscope; As the floating bearing block I00 is moved up and down by means of the fine adjustment mechanism to be described; the shaft I2 5 will move upand down in the slot I2 lof the drive member P29.

. sequently, this bearingicanibe made much longer The fine adjustmentmechanis-m shown in Figs. 7

8 to 11' is similar in construction to the one described in connection with Figs. 1' to. 7, and ineludes a pair of coarse adjustment buttons I30 or other actuating means, mounted onthe' opposite ends ofa fine adjustment shaft I31 which extends through the hollow coarse adjustment shafts HI and H2. This line adjustment: shaft l tl', Fig. 8; has a screw-threaded portionwhich tons I38; the'fi'ne adjustment lever I35 will-be swung through the: medium: of? theme? adjust mentnunlfiz andiaring 133: to-raise or lower the floating: bearing; blockrlfn 01': During: the raising and lowering of this block, the floating connectionibetwe'en' the shaft I'2 5 andatlie: drive member t2?!) maintains: a, 1 driving? connection. between those parts: ozfs-the coarser adjustment: mechanism whichrare mountedzonz. the floating bearing. block 98 to hold the floating bearing block lflll in conr tact with! the short armrI-Sr'k of? the fineradjusttment lever, and: thus inaturn; holds the longer arm I '35 in engagement. with .thefine: adjustment ring I33.

Invthiswconstruction, as in that" describedr in connection withzFigs. 1 to--7,.-thes floating bearing block 100 isiconnected to the arm. 98 with suflicient friction to. enable thev arm to; be raised and lowered byraising and lowering the floating bear ing.block,. and this friction may lave-introduced iii-any suitableor desiredimanner; The two parts of the; block are secured: together by means-of screws.- I-44- which may draw the two partszof-the block; into-engagementwith opposite sides. of the guide track IYOI of the arm 98;; or. into engage.-

mentwith. the ends of the gears I04 and .lalJ 5-,.- or

into engagement: with the shatt I25 ofthe gear 1.2-6. By adjusting the tensio-nsonthez screws- M4,

the desired friction may beobtained, whichzrric tion canbe overcome by the; coarse adjustment mechanism,v but notbythe; fine adjustment mechanismm Bymeans of. 'the'constructions shown;.on-1y a single-bearing: is necessary between the: main frame and. thearm, and:.both= coarse and fine adjustments are-made along this bearing. C'Onithan usual, thus increasing-the: strength-on the instrument-and: adding. materiallyto the. accuracy and durability'of the same;

.sa-id main frameto move "saidi body tube toward and: from said stage; a. hollow. coarseadjustment shaft rotatablyimounted in said: frame, a:.fine adjustmentshattirotatably'mountedin:saidhoilnw coarse" adjustment shaft anda'havingoa threaded portion; means for. transmittingigrota-m motion 'of said coarse adjustment shaft: tossaid 'anrr'for rapid adjustment thereof, a sleeve; having. a longitudinal' slot: and: secured. to. said-coarse: 1 adjustment shatt, a-nut in. said sleeve which is threaded. to cooperate with the threaded'portion of" said fine adjustment; shaft, 2; ring; sli'd'ably mounted on: the

exterior of said: sleeve and: connected through the slot; of said:sleeve-with saidr.nutgand fmeansuco operating with; said ring-for: transmitting-irmove ment of.-said :ring to saidi'a-rm.:i

2. A microscope: including as'main frame; -a stage mounted on said? frame? albody ttube"; an arm carrying saidbody'tube: andimovably mount ed: 0n;said main: frame; .tor'move said body tube toward and:rromssaidz stage,.rar hollowboa'rse adjustment shaft rotatably mounted in said frame, afine adjustment shaft rotatably mounted in said hollow coarse adjustment shaft and having a threaded portion, means for transmitting rotary motion of saidcoarse adjustment shaft to said arm for rapid adjustment thereof, a nut having a threaded portion cooperating with the threaded portion of said fine adjustment shaft and held against rotation relatively to said coarse adjustment shaft and free to move lengthwise with refsleeve connecting said hollow coarse adjustment shafts and having a longitudinal slot, means for converting rotary motion of said hollow coarse adjustment shafts into longitudinal movement of said arm, a fine adjustment shaft extending through said hollow coarse adjustment shafts and having a threaded part, a threaded nut cooperating, with said threaded part and arranged within said slotted sleeve, a ring slidable on the exterior of said sleeve and connected with said nut through said slot, and means for transmitting motion of said ring to said arm independently of the adjustment of the same by said coarse adjustment. i

4. A microscope including a main frame, a

stage mounted on said frame, a body tube, an

. arm carrying said body tube and movably mounted on said main frame to move said body tube toward and from said stage, a hollow coarse adjustment shaft rotatably mounted in said frame, a fine adjustment shaft rotatably mounted in said hollow coarse adjustment shaft and having a threaded portion, a gear on said coarse adjustment shaft, means forconverting rotary motion of said gear into longitudinal motion of said arm, a nut having threads cooperating with the threaded portion of said fine adjustment shaft and held against rotation relatively to said coarse adjustment shaft and movable lengthwise relatively to said coarse adjustment shaft, and means for transmitting lengthwise movement of said nut to said arm independently of the adjustment thereof by said coarse adjustment shaft.

5. A microscope including a base, a mainframe having a pivotal connection with said base, a stage on said frame, a body tube carrying arm movably mounted on said main frame to move said body tube toward and from said stage, a hollowcoarse adjustment shaft mounted on said main frame concentric with said pivotal connection, a fine adjustment shaft rotatably mounted in said hollow coarse adjustment shaft, means for converting rotary motion of said coarse adjustment shaft into longitudinal movement of said arm, a nut held against rotation relatively'to said coarse adjustment shaft and movable lengthwise thereof and having a threaded portion cooperating with the threaded portion of said fine adjustment shaft, and means for transmitting movement of said nut to said arm to move the same independently of said coarse adjustment shaft.

6. A microscope including a frame, a body tube supporting arm, bearing means on said frame and arm forming a slidable connection between said frame and arm, a bearing block slidably mounted on saidarm, a coarse adjustment mechanism having a partjournalled in said bearing block and re-.

acting against said arm for adjusting said arm i on said bearing means relatively to said block and frame while said block remains in fixed relation to said frame, and a fine adjustment mechanism having a movable part for supporting said block and for moving said block and arm relatively to said frame on saidbearing means, said coarse and fine adjustment mechanisms including adjustment shafts journalled on said frame to rotate about a common axis.

17. A microscope including a frame, a body tube supporting arm, bearing means on said frame and arm forming a slidable connection between said frame and arm, a bearing block slidably mounted and frictionally held on said arm, coarse adjustmentmeans including a part journalled on said block and reacting against said arm for mov-. ing said arm in said bearing means relatively to said bearing block against the friction while said block remains in fixed relationto said frame,

and fine adjustment means formoving said bearingblock and arm on said bearing means, said having a part journalled in said bearing block and another part journalled in said frame,-a floating connection between said partsof said coarse adjustment mechanism, and a fine adjustment mechanism having a movable part forsupporting said block and for moving said block, said arm and said part of said coarse adjustment mechanism journalled in said block, on said bearing means, said arm being held against movement relatively to said block by friction during fine adjustments and being moved against friction by said coarse adjustment mechanism.

9. A microscope including a frame, a body tube supporting arm, bearing means on said frame and arm forming a slidable connection between said frame and arm, a bearing block slidably mounted on said arm, a rack secured to said arm, a coarse adjustment mechanism including a pinion pivoted on said block and meshing with said rack, and another part pivoted on said frame, a universal joint connection between said parts, and a fine adjustment mechanism for moving said block and armrelatively to said frame.

10. A microscope including a frame, a body tube supporting arm, bearing means on said frame and arm forming a slidable connection between said frame and arm, a bearing block slidably mounted on said arm; a rack secured to said arm, a coarse adjustment mechanism including a pinion pivoted on said block and meshing with said rack and another part pivoted on said frame, and a floating connection between said parts, including a shaft connected to rotate with and slide lengthwise of said other part, and a fine adjustment mechanism for moving said block and arm relatively to said frame.

11. A microscope including a frame, a body tube supporting arm, bearing means on saidarm, a. coarse-adjustmentmechanismlinchidingta I pinion, and an; actuating :shaft therefor. pivoted on said bearing block anddmovable therewith, and a'shaft on thea'frame connectedztova'ctuatez said first mentioned xshaft, rand: ha 5. fine .zad'justment meehanism;v supporting: said :rblock'a an'd iiconstructed to move the same and-:saidrarm.

.12. A 'r microscope," including a': main I frame, u a stage rm'ounted ron' :said: frame, a bOfiy; tube, can arm icarrying :said vbody ;'tube.rland imovably mounted-:ona saidi main: frame to. movensaid .body tube toward and from 1said:1stage,;' a'fpaircof' hollowtcoarse: adjustmentlsh'aftsf journalledi'in. said main frame and extending toward opposite:sides thereof, =azsl'eeve: connecting: saidxholl'ow' coarse adj ustmentshafts: and having; a longitudinal :slot, means? f or: converting. rotary'imotiomof: saidi'hollow. course adjustment, ishafts; into longitudinal movement of said zarm,; a fine. adjustment: shaft extending through-said hol'low coarseadjustment shafts and." having 2a threaded .part, 1 -.a 5. threaded nut. cooperating withsaid;threadedi'partizandarranged within said slotted; sleeve and 1 between thez'inner ends' ofasaid "coarse adjustment shafts, the ends of said coarse adjustment shaftsserving to limit the: movement I of 1 said nut said sleeve,-a'ring slida-ble' on the-exterior of said-sleeve and connected with: said nut through said slot, and means for transmitting: motion of said ring to said arm independently of the adjustment of the=same bysaidcoarse adjustment.

j 13. "A -microscope" having a body tube sup-porting-arm adjustablymounted on the frame ofthe microscope for-"moving the body tube' toward and from the rspecimenya rotatable "slotted" hollow sleeve 'having a *gear mounted thereon to rotate therewith, means driven 'bysai'd gear f or effecting coarse adjustment 1 -of -=said arm when said sleeve is turned: a'fine'adjustment nut within said sleeve, a "threaded "fine "adjustment -shaft having' a threaded part= engaging said nut, and means'exten'ding through the slot of said sleeve for -holding said nut against turning relatively to-said sleeve -and*'for transmitting movement ofsaid' nutlengthWise of said-sleeve to said arm for effecting" fine adjustment thereof.

14. '-A*microscope" including a I main frame, a body tube carrying arm slid'able in a substantially vertical direction 'onsaid main frame for adjusting; the body tube-"relatively to aspecimen,

a :hollow coarse adjustment v-shaft rotatably mounted in: said: frame, a fine adjustment shaft rotatably mountedlin said hollow coarse adjustment shaft-.means for transmitting rotary, mo.-

' tion of saidcoarsezadjustment shaft. to. said; arm

forrapi'dz-xadjustment thereof relatively-to said frame, :a. sleeve. secured: to said coarse adjustment shaft,- a ring slidably "mounted, on the exterior of'saidssleevameansr actuated by said fine adjustmentrshaft-forimovingsaid ring lengthwise of said sleeve, and". means; cooperating'with said ring for transmitting movement of: said ring lengthwise of said sleeve to said arm for effecting fine adjust-ment thereof.

'15. "A'microscop including a mainframe, a body tube'carrying arm slidable in' a substantially vertical direction on said mainframe for'adjusting'thebo'dytube relatively to a specimen, a hollow course adjustment shaft rotatably mounted in said frame, 'a fine adjustment shaft rotatably mounted in said hollow coarse adjustment shaft, means for transmitting rotary motion of'said course adjustment shaft to said arm for rani'dadjustment thereof relatively to said frame, a ring arranged concentrically with said shafts, means connecting said fine-adjustmentshaft and said ring for moving saidring-axially relatively to said shafts, and means cooperating with said ring for transmitting axial movement of said ring to said arm for effectingfine adjustment thereof.

16. A microscope including a. main frame, a body tubeicarrying arm slidable' in. a substantially vertical directionon said'main frame, for adjusting the body tube relatively to a specimen, a 'hollow'coarse adjustment shaft rotatably mounted in said'frame, a fine adjustment, shaft rotatably mounted in said hollow coarse. adjustment shaft andlhaving a threaded portion, .meansfor transmitting rotary motionof saidcoarseadjustment shaft to said 'arm for rapid. adjustment thereof relatively to said frame, a. ring mounted to rotate with said coarse adjustment shaft and to move axially thereof,.means-. connected with the threaded portionof saidfine. adjustmentshaft for moving said ring axially of; said coarse adjustment shaft,. .and .meanscooperating. with said ring 'for transmitting axial movement .of .said ring to said arm.

I-IARVEY N. 

